I had same problem. Ivd had asthma for 10 years but never had to take medicine everyday. 14 months ago had real problem breathing, it felt like bad asthma. Ive done a ton of PFTs and chest xrays and my lungs are good. I found out i had refux and had the surgery 2 months ago. Im still not better. Im going to Cleveland Clinic in 2 weeks to figure it out. There are many others on here with our problem, we all get tests done, and they all come back normal. We are all begging for help. They try to tell you its anxiety or in your head. I ve tried every med, none work. Im at the end of my rope.
My daughter was micro-aspirating at night (reflux aspiration) and once it got under control so did the asthma and that was yrs of Flovent, Singulair, inhalers, Prednisone! Her trigger was cat ...... once the cat passed away (20yrs old) so did her asthma improve ten-fold and so did her reflux .. Prilosec worked for her.
Have you considered a total food elimination diet ? That would be total and add in one more thing ev. 3 days .... not just making changes here or there ? Sometimes that will pinpoint the severe allergy/intolerance?
C~
Maybe a Flovent Inhaler will help you, it helps heal your lungs. Some suffering from childhood asthma develop acid reflux later in life.
The next step if you're not able to control what is going on may have to be some form of either endoscopic treatment or perhaps surgical control in the form of the Nissen fundoplication. You might want to consider endoscopic means first and if you can't control things then, it possible you might be able to then consider the Nissen. You'd have to undergo all the tests, however, to make sure you're a good candidate.